An optical network uses optical signals to communicate information among the nodes of the network. This information often includes both data (e.g., a file that is being downloaded, packets carrying voices of a phone call, or the contents of a webpage) and signaling (e.g., commands or messages between nodes containing status or setup information). In some optical networks the data may be transferred using a data channel (e.g., a datalink) while the signaling is communicated using a control channel. In such an instance the control channel may be said to be out-of-band; that is the control channel is separate from the data channel. In some situations, such as in an optical network comprising several nodes, it may be desirable for a node to have multiple control channels. However, some protocols, such as the Link Management Protocol (LMP), have limited control in managing multiple control channels over a single physical interface.
Generic multi-protocol label switching requires out-of-band control channels in order to be able to control a non-IP based network element such as an optical network element. LMP maintains control channels which can be identified as a pair of unique IP addresses. Furthermore, LMP requires multiple or redundant control channels between two nodes for resiliency. However, LMP does not support multiple control channels between two indirectly connected nodes. One solution is to create generic routing encapsulation, or IP-in-IP tunnels, in order to achieve logical separation between a data channel and a control channel. However, this often requires universal support of the tunneling feature.